Silver halide photographic receivers contain light sensitive silver halide in a hydrophilic emulsion. An image is formed in the receiver by exposing the silver halide to light, or to other actinic radiation, and developing the exposed silver halide to reduce it to elemental silver.
In color photographic receivers a dye image is formed as a consequence of silver halide development by one of several different processes. The most common is to allow a by-product of silver halide development, oxidized silver halide developing agent, to react with a dye forming compound called a coupler. The silver and un-reacted silver halide are then removed from the photographic receiver, leaving a dye image.
The formation of the dye image commonly involves liquid processing with aqueous solutions that must penetrate the surface of the receiver to come into contact with silver halide and coupler. Gelatin and similar natural or synthetic hydrophilic polymers have been the common binder of choice for silver halide photographic receivers. Unfortunately, when gelatin and other similar polymers are not durable and mar-resistant enough for handling. The imaged receiver can be marked by fingerprints, it can be scratched or torn, it can also deform, swell or form image artifact when it is contacted with liquids.
Various coating techniques have been developed to provide a protection layer over the silver halide images. Some of these techniques require wet chemical coating and radiation treatment. Some of these techniques require the use of fusing particles and/or the use of electrostatic field. These operations are costly and complex.
The silver halide photographic images can also be protected by a lamination sheet. The lamination method suffer the following several drawbacks: first, the lamination sheet significantly increases the cost of the media per unit area. Second, the lamination machine is expensive. Third, the lamination has the tendency to delaminate over time or under physical or heat disturbance.
There remains a need for a simple, low-cost, and dry process for providing protection on photographic images without the drawbacks of the above described techniques.